This invention generally relates to novel compounds, pharmaceutical compositions and their use. This invention more specifically relates to novel heterocyclic compounds that bind to chemokine receptors, including CXCR4 and CCR5, and demonstrate protective effects against infection of target cells by a human immunodeficiency virus (HIV).
Approximately 40 human chemokines have been described, that function, at least in part, by modulating a complex and overlapping set of biological activities important for the movement of lymphoid cells and extravasation and tissue infiltration of leukocytes in response to inciting agents (See, for example: P. Ponath, Exp. Opin. Invest. Drugs, 7:1-18, 1998; Baggiolini, M., Nature 392:565-568 (1998); Locati, et al., Annu. Rev. Med. 50:425-440 (1999)). These chemotactic cytokines, or chemokines, constitute a family of proteins, approximately 8-10 kDa in size. Chemokines appear to share a common structural motif, that consists of 4 conserved cysteines involved in maintaining tertiary structure. There are two major subfamilies of chemokines: the xe2x80x9cCCxe2x80x9d or xcex2-chemokines and the xe2x80x9cCXCxe2x80x9d or xcex1-chemokines. The receptors of these chemokines are classified based upon the chemokine that constitutes the receptor""s natural ligand. Receptors of the xcex2-chemokines are designated xe2x80x9cCCRxe2x80x9d while those of the xcex1-chemokines are designated xe2x80x9cCXCRxe2x80x9d.
Chemokines are considered to be principal mediators in the initiation and maintenance of inflammation (see Chemokines in Disease published by Humana Press (1999), Edited by C. Herbert; Murdoch, et al., Blood 95:3032-3043 (2000)). More specifically, chemokines have been found to play an important role in the regulation of endothelial cell function, including proliferation, migration and differentiation during angiogenesis and re-endothelialization after injury (Gupta, et al., J. Biol. Chem., 7:4282-4287 (1998); Volin, et al., Biochem. Biophys Res. Commun. 242:46-53 (1998)). Two specific chemokines have been implicated in the etiology of infection by human immunodeficiency virus (HIV).
In most instances, HIV initially binds via its gp120 envelope protein to the CD4 receptor of the target cell. A conformational change appears to take place in gp120 which results in its subsequent binding to a chemokine receptor, such as CCR5 (Wyatt, et al., Science, 280:1884-1888 (1998); Rizzuto, et al., Science, 280:1949-1953 (1998); Berger, et al., Annu. Rev. Immunol. 17:657-700 (1999)). HIV-1 isolates arising subsequently in the infection bind to the CXCR4 chemokine receptor.
Following the initial binding by HIV to CD4, virus-cell fusion results, which is mediated by members of the chemokine receptor family, with different members serving as fusion cofactors for macrophage-tropic (M-tropic) and T cell line-tropic (T-tropic) isolates of HIV-1 (Carroll, et al., Science, 276:273-276 (1997); Feng, et al., Science 272:872-877 (1996); Bleul, et al., Nature 382:829-833 (1996); Oberlin, et al., Nature 382:833-835 (1996); Cocchi, et al., Science 270:1811-1815 (1995); Dragic, et al., Nature 381:667-673 (1996); Deng, et al., Nature 381:661-666 (1996); Alkhatib, et al., Science 272:1955-1958 (1996). During the course of infection within a patient, it appears that a majority of HIV particles shift from the M-tropic to the more pathogenic T-tropic viral phenotype (Blaak, et al., Proc. Natl. Acad. Sci. 97:1269-1274 (2000); Miedema, et al., Immune. Rev., 140:35 (1994); Simmonds, et al., J. Virol. 70:8355-8360 (1996); Tersmette, et al., J. Virol. 62:2026-2032 (1988); Connor, R. I., Ho, D. D. J. Virol. 68:4400-4408 (1994); Schuitemaker, et al., J. Virol. 66:1354-1360 (1992)). The M-tropic viral phenotype correlates with the virus""s ability to enter the cell following binding of the CCR5 receptor, while the T-tropic viral phenotype correlates with viral entry into the cell following binding and membrane fusion with the CXCR4 receptor. Clinical observations suggest that patients who possess genetic mutations in CCR5 appear resistant, or less susceptible to HIV infection (Liu, et al., Cell 86:367-377 (1996); Samson, et al., Nature 382:722-725 (1996); Michael, et al., Nature Med. 3:338-340 (1997); Michael, et al., J. Virol. 72:6040-6047 (1998); Obrien, et al., Lancet 349:1219 (1997); Zhang, et al., AIDS Res. Hum. Retroviruses 13:1357-1366 (1997); Rana, et al., J. Virol. 71:3219-3227 (1997); Theodorou, et al., Lancet 349:1219-1220 (1997). Despite the number of chemokine receptors which have been reported to HIV mediate entry into cells, CCR5 and CXCR4 appear to be the only physiologically relevant coreceptors used by a wide variety of primary clinical HIV-1 strains (Zhang, et al., J. Virol. 72:9307-9312 (1998); Zhang, et al., J. Virol. 73:3443-3448 (1999); Simmonds, et al., J. Virol. 72:8453-8457 (1988)). Fusion and entry of T-tropic viruses that use CXCR4 are inhibited by the natural CXC-chemokine stromal cell-derived factor-1, whereas fusion and entry of M-tropic viruses that use CCR5 are inhibited by the natural CC-chemokines namely, Regulated on Activation Normal T-cell Expressed and Secreted (RANTES) and Macrophage Inflammatory proteins (MIP-1 alpha and beta).
In addition to serving as a co-factor for HIV entry, the direct interaction of virus-associated gp120 with CXCR4 has been recently suggested as a possible cause of CD8+ T-cell apoptosis and AIDS-related dementia via induction of neuronal cell apoptosis (Hesselgesser, et al., Curr. Biol. 8:595-598 (1998); Hesselgesser, et al., Curr. Biol. 7:112-121 (1997); Hesselgesser, et al., xe2x80x9cChemokines and Chemokine receptors in the Brainxe2x80x9d in Chemokines in Disease published by Humana Press (1999), Edited by C. Herbert; Herbein, et al., Nature 395:189-194 (1998); Buttini, et al., Nature Med. 4:441-446 (1998); Ohagen, et al., J. Virol. 73:897-906 (1999); Biard-Piechaczyk, et al., Virology 268:329-344 (2000); Sanders, et al., J. Neuroscience Res. 59:671-679 (2000); Bajetto, et al., J. Neurochem. 73:2348-2357 (1999); Zheng, et al., J. Virol. 73:8256-8267 (1999)).
However, the binding of chemokine receptors to their natural ligands appears to serve a more evolutionary and central role than only as mediators of HIV infection. The binding of the natural ligand, pre-B-cell growth-stimulating factor/stromal cell derived factor (PBSF/SDF-1) to the CXCR4 chemokine receptor provides an important signaling mechanism: CXCR4 or SDF-1 knock-out mice exhibit cerebellar, cardiac and gastrointestinal tract abnormalities and die in utero (Zou, et al., Nature, 393:591-594 (1998); Tachibana, et al., Nature, 393:591-594 (1998); Nagasawa, et al., Nature 382:635-638 (1996)). CXCR4-deficient mice also display hematopoietic defects (Nagasawa, et al., Nature 382:635-638 (1996)); the migration of CXCR4 expressing leukocytes and hematopoietic progenitors to SDF-1 appears to be important for maintaining B-cell lineage and localization of CD34+ progenitor cells in bone marrow (Bleul, et al., J. Exp. Med. 187:753-762 (1998); Viardot, et al., Ann. Hematol. 77:195-197 (1998); Auiti, et al., J. Exp. Med. 185:111-120 (1997); Peled, et al., Science 283:845-848 (1999); Qing, et al., Immunity 10:463-471 (1999); Lataillade, et al., Blood 95:756-768 (1999); Ishii, et al., J. Immunol. 163:3612-3620 (1999); Maekawa, et al., Internal Medicine 39:90-100 (2000); Fedyk, et al., J. Leukocyte Biol. 66:667-673 (1999); Peled, et al., Blood 95:3289-3296 (2000)).
The signal provided by SDF-1 on binding to CXCR4 may also play an important role in tumor cell proliferation and regulation of angiogenesis associated with tumor growth (See xe2x80x9cChemokines and Cancerxe2x80x9d published by Humana Press (1999); Edited by B. J. Rollins; Arenburg, et al., J. Leukocyte Biol. 62:554-562 (1997); Moore, et al., J. Invest. Med. 46:113-120 (1998); Moore, et al., Trends cardiovasc. Med. 8:51-58 (1998); Seghal, et al., J. Surg. Oncol. 69:99-104 (1998)); the known angiogenic growth factors VEG-F and bFGF, up-regulate levels of CXCR4 in endothelial cells, and SDF-1 can induce neovascularization in vivo (Salcedo, et al., Am. J. Pathol. 154:1125-1135 (1999)); Leukemia cells that express CXCR4 migrate and adhere to lymph nodes and bone marrow stromal cells that express SDF-1 (Burger, et al., Blood 94:3658-3667 (1999); Arai, et al., Eur. J. Haematol. 64:323-332 (2000); Bradstock, et al., Leukemia 14:882-888 (2000)).
The binding of SDF-1 to CXCR4 has also been implicated in the pathogenesis of atherosclerosis (Abi-Younes, et al., Circ. Res. 86:131-138 (2000)), renal allograft rejection (Eitner, et al., Transplantation 66:1551-1557 (1998)), asthma and allergic airway inflammation (Yssel, et al., Clinical and Experimental Allergy 28:104-109 (1998); J. Immunol. 164:5935-5943 (2000); Gonzalo, et al., J. Immunol. 165:499-508 (2000)), Alzheimer""s disease (Xia, et al., J. Neurovirology 5:32-41 (1999)) and Arthritis (Nanki, et al., J. Immunol. 164:5010-5014 (2000)).
In attempting to better understand the relationship between chemokines and their receptors, recent experiments to block the fusion, entry and replication of HIV via the CXCR4 chemokine receptor were carried out through the use of monoclonal antibodies or small molecules that appear to suggest a useful therapeutic strategy (Schols, et al., J. Exp. Med. 186:1383-1388 (1997); Schols, et al., Antiviral Research 35:147-156 (1997); Bridger, et al., J. Med. Chem. 42:3971-3981 (1999); Bridger, et al., xe2x80x9cBicyclam Derivatives as HIV Inhibitorsxe2x80x9d in Advances in Antiviral Drug Design Vol. 3:161-229; Published by JAI press (1999); Edited by E. De Clercq). Small molecules, such as bicyclams, appear to specifically bind to CXCR4 and not CCR5 (Donzella, et al., Nature Medicine, 4:72-77 (1998)). These experiments demonstrated interference with HIV entry and membrane fusion into the target cell in vitro. More recently, bicyclams were also shown to inhibit fusion and replication of Feline Immunodeficiency Virus that uses CXCR4 for entry (Egberink, et al., J. Virol. 73:6346-6352 (1999)).
Additional experiments have shown that the bicyclam dose-dependently inhibits binding of 125I-labeled SDF-1 to CXCR4 and the signal transduction (indicated by an increase in intracellular calcium) in response to SDF-1. Thus, the bicyclam also functioned as an antagonist to the signal transduction resulting from the binding of stromal derived factor or SDF-1xcex1, the natural chemokine to CXCR4. Bicyclarns also inhibited HIV gp120 (envelope)-induced apoptosis in non-HIV infected cells (Blanco, et al., Antimicrobial Agents and Chemother. 44:51-56 (2000)).
U.S. Pat. Nos. 5,583,131; 5,698,546; and 5,817,807, which are herein incorporated in their entirety by reference, disclose cyclic compounds that are active against HIV-1 and HIV-2 in in vitro tests. It was subsequently discovered and further disclosed in copending application U.S. Ser. No. 09/111,895 and U.S. Ser. No. 60/172,153 that these compounds exhibit anti-HIV activity by binding to the chemokine receptor CXCR4 expressed on the surface of certain cells of the immune system. This competitive binding thereby protects these target cells from infection by HIV which utilize the CXCR4 receptor for entry. In addition, these compounds antagonize the binding, signaling and chemotactic effects of the natural ligand for CXCR4, the chemokine stromal cell-derived factor 1xcex1. (SDF-1). We further disclosed that these novel compounds demonstrate protective effects against HIV infection of target cells by binding in vitro to the CCR5 receptor.
Additionally we have disclosed in U.S. Ser. No. 09/495,298 that these cyclic polyamine antiviral agents described in the above-mentioned patents have the effect of enhancing production of white blood cells as well as exhibiting antiviral properties. Thus, these agents are useful for controlling the side-effects of chemotherapy, enhancing the success of bone marrow transplantation, enhancing wound healing and burn treatment, as well as combating bacterial infections in leukemia.
More recently, we disclosed in PCT International Application PCT/CA00/00321, a series of heterocyclic compounds that exhibit anti-HIV activity by binding to the chemokine receptors CXCR4 and CCR5 expressed on the surface of certain cells of the immune system. This competitive binding thereby protects these target cells from infection by HIV which utilize the CXCR4 or CCR5 receptors for entry. In addition, these compounds antagonize the binding, signaling and chemotactic effects of the natural ligand for CXCR4, the chemokine stromal cell-derived factor 1xcex1 (SDF-1) and/or the natural ligand for CCR5, the chemokine RANTES.
Herein, we disclose novel compounds that exhibit protective effects against HIV infection of target cells by binding to the chemokine receptors CXCR4 or CCR5, in a similar manner to the previously disclosed macrocyclic compounds.
Citation of the above documents is not intended as an admission that any of the foregoing is pertinent prior art. All statements as to the date or representation as to the contents of these documents is based on the information available to the applicants and does not constitute any admission as to the correctness of the dates or contents of these documents. Further, all documents referred to throughout this application are hereby incorporated in their entirety by reference herein.
The present invention provides novel compounds that bind chemokine receptors and interfere with the binding of the natural ligand thereto. The compounds of the present invention are useful as agents demonstrating protective effects on target cells from HIV infection. Other embodiments of the present invention are compounds that act as antagonists or agonists of chemokine receptors, as well as other biological activities related to the ability of these compounds to inhibit the binding of chemokines to their receptors.
The compounds of the invention are of the formula 
and the salts and prodrug forms thereof,
wherein:
X is a monocyclic (5-6 membered) or fused bicyclic (9-12 membered) unsubstituted or substituted ring system containing at least one heteroatom selected from N, O and S;
Z is H, or is a monocyclic (5-6 membered) or fused bicyclic (9-12 membered) unsubstituted or substituted ring system containing at least one heteroatom selected from N, O and S;
Ar is an optionally substituted aromatic or heteroaromatic ring;
each of L1, L2 and L3 is independently a bond, CO, SO2, or CH2, wherein at least one of L2 and L3 must comprise CO or SO2; and wherein L1 can also be alkylene (2-5C) wherein one or two C may optionally be replaced by N and which alkylene may itself optionally be substituted by a bridge alkylene (3-4C); L2 and L3 also may be, independently, SO2NH, CONH, SO2NHCH2 or CONHCH2;
n is 0, 1 or 2;
each R1 and R2 is independently H or straight or branched chain or cyclic alkyl (1-6C) which may optionally be substituted, and wherein R2 may be alkylene coupled to Y; and
Y comprises at least one aromatic or heteroaromatic or other heterocyclic substituted or unsubstituted ring coupled directly to L3.
The invention is directed to the compounds of formula 1 above, and to the use of these compounds in treating and in the preparation for medicaments for treating conditions which are affected by modulating the CXCR4 and/or CCR5 receptors.
The present invention is directed to compounds of Formula I which can act as agents that modulate chemokine receptor activity. Such chemokine receptors include but are not limited to CCR1, CCR2, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8 and CXCR1, CXCR2, CXCR3, CXCR4 and CXCR5.
The present invention provides novel compounds of Formula I that demonstrate protective effects on target cells from HIV infection in a manner as to bind specifically to the chemokine receptor, and which affect the binding of a natural ligand or chemokine to a receptor such as CXCR4 and/or CCR5 of a target cell.
Compounds of Formula I are useful as agents which affect chemokine receptors, such as CCR1, CCR2, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8 and CXCR1, CXCR2, CXCR3, CXCR4 and CXCR5 where such chemokine receptors have been correlated as being important mediators of many human inflammatory as well as immunoregulatory diseases. Thus, a compound that modulates the activity of such chemokine receptors would be useful for the treatment or prevention of such diseases.
The term xe2x80x9cmodulatorsxe2x80x9d as used herein is intended to encompass antagonist, agonist, partial antagonist, and or partial agonist, inhibitors, and activators. In one preferred embodiment of the present invention, compounds of Formula I demonstrate protective effects against HIV infection by inhibiting the binding of HIV to a chemokine receptor such as CXCR4 and/or CCR5 of a target cell. The invention includes a method which comprises contacting the target cell with an amount of the compound which is effective at inhibiting the binding of the virus to the chemokine receptor.
Compounds that inhibit chemokine receptors may be used for the treatment of diseases associated with hematopoiesis, including but not limited to, controlling the side-effects of chemotherapy, enhancing the success of bone marrow transplantation, enhancing wound healing and burn treatment, as well as combating bacterial infections in leukemia.
Compounds that inhibit chemokine receptor activity and function may be used for the treatment of diseases that are associated with inflammation, including but are not limited to, inflammatory or allergic diseases such as asthma, allergic rhinitis, hypersensitivity lung diseases, hypersensitivity pneumonitis, eosinophilic pneumonias, delayed-type hypersensitivity, interstitial lung disease (ILD) (e.g., idiopathic pulmonary fibrosis, or ILD associated with rheumatoid arthritis, systemic lupus erythematosus, ankylosing spondylitis, systemic sclerosis, Sjogren""s syndrome, polymyositis or dermatomyositis); systemic anaphylaxis or hypersensitivity responses, drug allergies, insect sting allergies; autoimmune diseases, such as rheumatoid arthritis, psoriatic arthritis, systemic lupus erythematosus, myastenia gravis, juvenile onset diabetes; glomerulonephritis, autoimmune throiditis, graft rejection, including allograft rejection or graft-versus-host disease; inflammatory bowel diseases, such as Crohn""s disease and ulcerative colitis; spondyloarthropathies; scleroderma; psoriasis (including T-cell mediated psoriasis) and inflammatory dermatoses such as dermatitis, eczema, atopic dermatitis, allergic contact dermatitis, urticaria, vasculitis (e.g., necrotizing, cutaneous, and hypersensitivity vasculitis); eosinphilic myotis, eosiniphilic fasciitis; and cancers.
Compounds that activate or promote chemokine receptor function may be used for the treatment of diseases that are associated with immunosuppression such as individuals undergoing chemotherapy, radiation therapy, enhanced wound healing and burn treatment, therapy for autoimmune disease or other drug therapy (e.g., corticosteroid therapy) or combination of conventional drugs used in the treatment of autoimmune diseases and graft/transplantation rejection, which causes immunosuppression; immunosuppression due to congenital deficiency in receptor function or other causes; and infectious diseases, such as parasitic diseases, including but not limited to helminth infections, such as nematodes (round worms); Trichuriasis, Enterobiasis, Ascariasis, Hookworm, Strongyloidiasis, Trichinosis, filariasis; trematodes; visceral worms, visceral larva migtrans (e.g., Toxocara), eosinophilic gastroenteritis (e.g., Anisaki spp., Phocanema ssp.), cutaneous larva migrans (Ancylostona braziliense, Ancylostoma caninum); the malaria-causing protozoan Plasmodium vivax, Human cytomegalovirus, Herpesvirus saimiri, and Kaposi""s sarcoma herpesvirus, also known as human herpesvirus 8, and poxvirus Moluscum contagiosum. 
It will be understood that that compounds of Formula I may be used in combination with any other pharmaceutical composition where such combined therapy may be useful to modulate chemokine receptor activity and thereby prevent and treat inflammatory and immunoregulatory diseases.
It is also contemplated that the present invention may be used in combinations with one or more agents useful in the prevention or treatment of HIV. Examples of such agents include:
(1) nucleotide reverse transcriptase inhibitor such as zidovudine, didanosine, lamivudine, zalcitabine, abacavir, stavudine, adefovir, adefovir dipivoxil, fozivudine todoxil, etc.;
(2) non-nucleotide reverse transcriptase inhibitor (including an agent having anti-oxidation activity such as immunocal, oltipraz, etc.) such as nevirapine, delavirdine, efavirenz, loviride, immunocal, oltipraz, etc.; and
(3) protease inhibitors such as saquinavir, ritonavir, indinavir, nelfinavir, amprenavir, palinavir, lasinavir, etc.
The scope of combinations of compounds of Formula I of this invention with HIV agents is not limited to (1), (2), and or (3), but includes in principle, any combination with any pharmaceutical composition useful for the treatment of HIV. Further, in such combinations the compounds of the present invention and other HIV agents may be administered separately or in conjunction. In addition, the administration of one element may be prior to, concurrent to, or subsequent to the administration of other agent(s).
The compounds of Formula I in the present invention may be administered by oral, parenteral (e.g., intramuscular, intraperitoneal, intravenous, intracisternal injection or infusion, subcutaneous injection, or implant), by inhalation spray, nasal, vaginal, rectal, sublingual, or topical routes of administration and may be formulated, alone or together, in suitable dosage unit formulations containing conventional non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles appropriate for each route of administration.
The compounds of Formula I are all active and used to treat animals, including mice, rats, horses, cattle, sheep, dogs, cats, and monkey. The compounds of the invention are also effective for use in humans.
The compounds of Formula I of the present invention may form hydrates or solvates. When the compounds of Formula I of the present invention exist as regioisomers, configurational isomers, conformers, diasteroisomeric forms and mixtures of diasteroisomeric forms thereof, it is possible to isolate individual isomers using known separation and purification methods, if desired. When the compound of Formula I of the present invention is racemate, it can be separated into the (S)-compound and (R)-compound by optical resolution. Individual optical isomers and a mixture thereof are included in the scope of the present invention.
This invention also relates to a pharmaceutical composition comprising a pharmaceutically acceptable carrier or diluent and an effective amount of compound of Formula I. A compound of Formula I may be administered alone or as an admixture with a pharmaceutically acceptable carrier (e.g., solid formulations such as tablets, capsules, granules, powders, etc.; liquid formulations such as syrups, injections, etc.) may be orally or non-orally administered. Examples of non-oral formulations include injections, drops, suppositories, pessaryies.
In the treatment or prevention of conditions which require chemokine receptor modulation an appropriate dosage level will generally be about 0.01 to 500 mg per kg patient body weight per day which can be administered in singe or multiple doses. Preferably, the dosage level will be about 0.1 to about 250 mg/kg per day. It will be understood that the specific dose level and frequency of dosage for any particular patient may be varied and will depend upon a variety of factors including the activity of the specific compound used, the metabolic stability and length of action of that compound, the age, body weight, general health, sex, diet, mode and time of administration, rate of excretion, drug combination, the severity of the particular condition, and the patient undergoing therapy.
The present invention further provides novel compounds that bind chemokine receptors and interfere with the binding of the natural ligand thereto. The compounds of the present invention are useful as agents demonstrating protective effects on target cells from HIV infection. The compounds of the present invention are also useful as antagonists or agonists of chemokine receptors, as well as other biological activities related to the ability of these compounds to inhibit the binding of chemokines to their receptors.
The compounds of the invention may be used as the xe2x80x9cpro-drugxe2x80x9d forms, that is, protected forms of the compounds, which release the compound after administration to a patient. For example, the compound may carry a protective groups which is split off by hydrolysis in body fluids e.g., in the bloodstream, thus releasing active compound or is oxidized or reduced in body fluids to release the compound. A discussion of pro-drugs may be found in xe2x80x9cSmith and Williams"" Introduction to the Principles of Drug Designxe2x80x9d, H. J. Smith, Wright, Second Edition, London 1988.
Acid addition salts, which are pharmaceutically acceptable, such as salt with inorganic base, a salt with organic base, a salt with inorganic acid, a salt with organic acid, a salt with basic or acidic amino acid, etc. are also encompassed in the present invention. Examples of a salt with an inorganic base include a salt with alkali metal (e.g., sodium, potassium, etc.), alkaline earth metal (e.g., calcium, magnesium, etc.), aluminum, ammonium, etc. Examples of the salt with an organic base include a salt with trimethylamine, triethylamine, pyridine, picoline, ethanolamine, diethanolamine, triethanolamine, dicyclohexylamine, N,Nxe2x80x2-dibenzylethylenediamine etc. Examples of the salt with an inorganic acid include a salt with hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, etc. Examples of the salt with an organic acid include a salt with formic acid, oxalic acid, acetic acid, tartaric acid, methanesulfonic acid, benzenesulfonic acid, malic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, etc. Examples of salts with basic amino acids include a salt with arginine, lysine, ornithine, etc. Examples of salts with the acidic amino acid include a salt with aspartic acid, glutamic acid, etc. Non-toxic in the present context has to be considered with reference to the prognosis for the infected patient without treatment.
Further Definition of the Compounds
X, Y and Z can be coupled to the remainder of the molecule through any ring position.
In one set of preferred embodiments of the present invention, L1 is a chemical bond.
In other preferred embodiments, Z comprises an optionally substituted aromatic or heteroaromatic group. In other preferred embodiments, Y comprises an unsubstituted heteroaromatic ring.
In one preferred set of embodiments, X or Z is a fused bicyclic system of the formula 
wherein m can be 0, 1 or 2.
In a another preferred embodiment of X or Z comprises a group of the formula 
which can be unsubstituted or substituted and wherein W is C, N, O or S. A particularly preferred embodiment is 
which may also be substituted or unsubstituted, but wherein Wxe2x95x90NH is preferred.
Other preferred forms include compounds of the formula 
or of the formula: 
wherein 1 is 0-3, and Rxe2x80x2 is OH, MeO, SH SMe, CN, CO2Me, F, Cl, Br, NO2, CH3CO, NH2, NHCH3, N(CH3)2, CH3CONH, CH3SO2NH, CONH2, SO2NH2, CF3, or Me;
each of Z1, Z2 and Z3 is independently CH, CRxe2x80x2 or N, wherein only two of said Z1, Z2 and Z3 can be N;
and L2 and L3 are as defined.
Still other preferred forms are compounds of the formula 
wherein 1 is 0-3, and Rxe2x80x2 is OH, MeO, SH SMe, CN, CO2Me, F, Cl, Br, NO2, CH3CO, NH2, NHCH3, N(CH3)2, CH3CONH, CH3SO2NH, CONH2, SO2NH2, CF3, or Me;
k is 0-2;
each of Z1, Z2 and Z3 is independently CH, CRxe2x80x2 or N, wherein only two of said Z1, Z2 and Z3 can be N;
and X, L2 and L3 are as defined.
In Formula I, examples of the optionally substituted ring system, X or Z, are dihydroquinoline, tetrahydroquinoline, pyranopyridine, dihydropyranopyridine, thiapyranopyridine, dihydrothiapyranopyridine, dihydronaphthyridine, and tetrahydronaphthyridine. Oxides of nitrogen and sulfur-containing heterocycles are also encompassed in the present invention. In the above ring system, any ring nitrogen atom may be substituted with hydrogen, a substituted alkyl, alkenyl, cycloalkyl or aryl group, or may be the nitrogen atom of a carboxamide, carbamate or sulfonamide. A preferred embodiment is tetrahydroquinoline.
In Formula I, the xe2x80x9coptional substituentsxe2x80x9d on X or Z may be halogen, nitro, cyano, carboxylic acid, an optionally substituted alkyl, alkenyl or cycloalkyl groups, an optionally substituted hydroxyl group, an optionally substituted thiol group, an optionally substituted amino or acyl group, an optionally substituted carboxylate, carbamate, carboxamide or sulfonamide group, an optionally substituted aromatic or heterocyclic group.
Examples of halogen include fluorine, chlorine, bromine, iodine, etc., with fluorine and chlorine preferred.
Examples of the optionally substituted alkyl include C1-10 alkyl, including methyl, ethyl propyl etc., examples of the optionally substituted alkenyl groups include, C2-10alkenyl such as allyl, crotyl, 2-pentenyl, 3-hexenyl, etc., and examples of the optionally substituted cycloalkyl groups include C3-10cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc. In these cases, C1-6alkyl, alkenyl and cycloalkyl are preferred. The optional substituent may also be an optionally substituted aralkyl (e.g., phenylC1-4 alkyl) or heteroalkyl for example, phenylmethyl (benzyl), phenethyl, pyridinylmethy, pyridinylethyl etc. The heterocyclic group may be a 5 or 6 membered ring containing 1-4 heteroatoms.
Examples of the optionally substituted hydroxyl and thiol groups include an optionally substituted alkyl (e.g., C1-10alkyl) such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl etc., preferably (C1-6) alkyl; an optionally substituted cycloalkyl (e.g., C3-7 cycloalkyl, etc. such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc.); an optionally substituted aralkyl (e.g., phenyl-C1-4alkyl, e.g., benzyl, phenethyl, etc.). Where there are two adjacent hydroxyl or thiol substituents, the heteroatoms may be connected via an alkyl group such as O(CH2)nO and S(CH2)nS (where n=1-5). Examples include methylenedioxy, ethylenedioxy etc. Oxides of thio-ether groups such as sulfoxides and sulfones are also encompassed.
Further examples of the optionally substituted hydroxyl group include an optionally substituted C2-4alkanoyl (e.g., acetyl, propionyl, butyryl, isobutyryl, etc.), C1-4alkylsulfonyl (e.g., methanesulfonyl, ethanesulfonyl, etc.) and an optionally substituted aromatic and heterocyclic carbonyl group including benzoyl, pyridinecarbonyl etc.
The substituents on the optionally substituted amino group may bind to each other to form a cyclic amino group (e.g., 5- to 6-membered cyclic amino, etc. such as tetrahydropyrrole, piperazine, piperidine, pyrrolidine, morpholine, thiomorpholine, pyrrole, imidazole, etc.). Said cyclic amino group may have a substituent, and examples of the substituents include halogen (e.g., fluorine, chlorine, bromine, iodine, etc.), nitro, cyano, hydroxy group, thiol group, amino group, carboxyl group, an optionally halogenated C1-4alkyl (e.g., trifluoromethyl, methyl, ethyl, etc.), an optionally halogenated C1-4alkoxy (e.g., methoxy, ethoxy, trifluoromethoxy, trifluoroethoxy, etc.), C2-4alkanoyl (e.g., acetyl, propionyl, etc.), C1-4alkylsulfonyl (e.g., methanesulfonyl, ethanesulfonyl, etc.) the number of preferred substituents are 1 to 3.
The amino group may also be substituted once or twice (to form a secondary or tertiary amine) with a group such as an optionally substituted alkyl group including C1-10alkyl (e.g., methyl, ethyl propyl etc.); an optionally substituted alkenyl group such as allyl, crotyl, 2-pentenyl, 3-hexenyl, etc., or an optionally substituted cycloalkyl group such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc. In these cases, C1-6alkyl, alkenyl and cycloalkyl are preferred. The amine group may also be optionally substituted with an aromatic or heterocyclic group, aralkyl (e.g., phenylC1-4alkyl) or heteroalkyl for example, phenyl, pyridine, phenylmethyl (benzyl), phenethyl, pyridinylmethyl, pyridinylethyl etc. The heterocyclic group may be a 5 or 6 membered ring containing 1-4 heteroatoms. The optional substituents of the xe2x80x9coptionally substituted amino groups are the same as defined above for the xe2x80x9coptionally substituted cyclic amino group.xe2x80x9d
The amino group may be substituted with an optionally substituted C2-4alkanoyl e.g., acetyl, propionyl, butyryl, isobutyryl etc., or a C1-4alkylsulfonyl (e.g., methanesulfonyl, ethanesulfonyl, etc.) or a carbonyl or sulfonyl substituted aromatic or heterocyclic ring, e.g., benzenesulfonyl, benzoyl, pyridinesulfonyl, pyridinecarbonyl etc. The heterocycles are as defined above.
Examples of the optionally substituted acyl group as the substituents on the fused ring system containing X include a carbonyl group or a sulfonyl group binding to hydrogen; an optionally substituted alkyl (e.g., C1-10alkyl such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, etc., preferably lower (C1-6) alkyl, etc.; an optionally substituted cycloalkyl (e.g., C3-7cycloalkyl, etc., such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc.); an optionally substituted alkenyl (e.g., C2-10alkenyl such as allyl, crotyl, 2-pentenyl, etc., preferably lower (C2-6) alkenyl, etc.); an optionally substituted cycloalkenyl (e.g., C3-7cycloalkenyl, etc., such as 2-cyclopentenyl, 2-cyclohexenyl, 2-cyclopentenylmethyl, 2-cyclohexenylmethyl, etc.) an optionally substituted 5- to 6-membered monocyclic aromatic group (e.g., phenyl, pyridyl, etc.).
Examples of the optionally substituted carboxylate group (ester groups) include an optionally substituted alkyl (e.g., C1-10alkyl such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, etc., preferably lower (C1-6) alkyl, etc.); an optionally substituted cycloalkyl (e.g., C3-7cycloalkyl, etc. such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc.); an optionally substituted alkenyl (e.g., C2-10alkenyl such as allyl, crotyl, 2-pentenyl, 3-hexenyl, etc., preferably lower (C2-6) alkenyl, etc.); an optionally substituted cycloalkenyl (e.g., C3-7cycloalkenyl, etc., such as 2-cyclohexenylmethyl, etc.); an optionally substituted aryl (e.g., phenyl, naphthyl, etc.) and C1-4aryl for example, benzyl, phenethyl etc. Groups such as methoxymethyl, methoxyethyl etc., are also encompassed.
Examples of the optionally substituted carboxamide and sulfonamide groups are identical in terms of the amine definition as the xe2x80x9coptionally substituted amino groupxe2x80x9d defined above.
Examples of the optionally substituted aromatic or heterocyclic groups as optional substituents are phenyl, naphthyl, or a 5- or 6-membered heterocyclic ring containing 1-4 heteroatoms. The optional substituents are essentially identical to those listed above.
In the above examples the number of substituents is 1-4, preferably 1-2. The substituents on the optionally substituted groups are the same as the optionally substituted groups described above. Preferred substituents are halogen (fluorine, chlorine etc.), nitro, cyano, hydroxy group, thiol group, amino group, carboxyl group, carboxylate group, sulfonate group, sulfonamide group, carboxamide group, an optionally halogenated C1-4alkyl, an optionally halogenated C1-4alkoxy (e.g., trifluoromethoxy, etc.), C2-4alkanoyl (e.g., acetyl, propionyl, etc.) or aroyl, a C1-4alkylsulfonyl (e.g., methanesulfonyl, ethanesulfonyl, etc.), an optionally substituted aryl or heterocyclic group. The number of substituents on the said groups are preferably 1 to 3.
In the above Formulas, W may be CH (pyrrole), O (oxazole), S (thiazole), NH or NRxe2x80x2 (imidazole) where Rxe2x80x2 is a C1-6alkyl group or acyl or sulfonyl group. Examples of fused ring systems that embody X or Z include but are not limited to indole, tetrahydroindole, benzimidazole, tetrahydrobenzimidazole, azabenzimidazole, benzoxazole, tetrahydrobenzoxazole, benzothiazole, tetrahydrobenzothiazole. Preferred ring systems are imidazole and benzimidazole.
In the above Formula I, Y is an optionally substituted heterocyclic group including a heteroaromatic group or aromatic group. Examples of the optionally substituted aromatic groups include benzene and naphthalene, or dihydronaphthalene and tetrahydronaphthalene. Examples of optionally substituted heterocyclic groups include 5 to 6-membered saturated, partially saturated, or aromatic heterocyclic rings containing 1 to 4 heteroatoms selected from nitrogen, oxygen and sulfur. The heterocycles may be pyridine, quinoline, isoquinoline, imidazole, benzimidazole, azabenzimidazole, benzotriazole, furan, benzofuran, thiazole, benzothiazole, oxazole, benzoxazole, pyrrole, indole, indoline, indazole, pyrrolidine, pyrrolidone, pyrroline, piperidine, piperazine, tetrahydroquinoline, tetrahydroisoquinoline, pyrazole, thiophene, isoxazole, isothiazole, triazole, tetrazole, oxadiazole, thiadiazole, morpholine, thiamorpholine, pyrazolidine, imidazolidine, imidazoline, tetrahydropyran, dihydropyran, benzopyran, dioxane, dithiane, tetrahydrofuran, tetrahydrothiophene, dihydrofuran, dihydrothiophene etc. Oxides of the nitrogen and sulfur containing heterocycles are also included in the present invention. The optional substituents for the fused or unfused aromatic or heterocyclic rings are identical to those described above.
When X or Z is of the formula A, B or C, optional substituents include additional ring systems such as cyclopentyl, cyclohexyl, cycloheptyl, tetrahydrofuran, tetrahydrothiophene (thiolane), tetrahydropyran, tetrahydrothiapyran (pentamethylene sulfide), phenyl, oxepine, thiepin, pyrollidine, piperidine, etc. Oxides of nitrogen and sulfur-containing heterocycles are also encompassed in the present invention. Other optional substituents are identical to the those described above.
The novel compounds of Formula I of the present invention may be formulated as pharmaceutical compositions that may be administered topically; percutaneously, including intravenously; orally; and by other standard routes of pharmaceutical administration to mammalian subjects as determined according to routine clinical practice.
Having now generally described the invention, the same will be more readily understood through reference to the following examples which are provided by way of illustration, and are not intended to be limiting of the present invention, unless specified.
General Procedure A: Direct Reductive Amination with NaBH3CN
To a stirred solution of the amine (1 equivalent) in anhydrous methanol (concentration xcx9c0.1 M), at room temperature, was added the carbonyl compound (xcx9c1-2 equivalents) in one portion. Once the carbonyl had dissolved (xcx9c5 minutes), NaBH3CN (xcx9c2-4 equiv.) was added in one portion and the resultant solution was stirred at room temperature. The solvent was removed under reduced pressure and CH2Cl2 (20 mL/mmol of amine) and brine or 1.0 M aqueous NaOH (10 mL/mmol amine) were added to the residue. The phases were separated and the aqueous phase was extracted with CH2Cl2 (3xc3x9710 mL/mmol amine). The combined organic phases were dried (Na2SO4) and concentrated. The crude material was purified chromatography.
General Procedure B: Direct Reductive Amination with NaBH(OAc)3 
To a stirred solution of the amine (1 equivalent) in CH2Cl2 (concentration xcx9c0.2 M), at room temperature, was added the carbonyl compound (xcx9c1-2 equivalents), glacial acetic acid (0-2 equivalents) and, NaBH(OAc)3 (xcx9c1.5-3 equiv.) and the resultant solution was stirred at room temperature. The reaction mixture was poured into either saturated aqueous NaHCO3 or 1.0 M aqueous NaOH (10 mL/mmol amine). The phases were separated and the aqueous phase was extracted with CH2Cl2 (3xc3x9710 mL/mmol amine). The combined organic phases were dried (Na2SO4) and concentrated. The crude material was purified chromatography.
General Procedure C: Deprotection of the 2-nitobenzenesulfonyl group (nosyl)
To a stirred solution of the nosyl-protected amine (1 equivalent) in anhydrous CH3CN (or DMF) (concentration xcx9c0.05 M), at room temperature, was added thiophenol (4-8 equiv.) followed by powdered K2CO3 (8-12 equivalents). The resulting bright yellow solution was stirred at room temperature (or 50xc2x0 C.) for 1-24 hours. The solvent was removed under reduced pressure and CH2Cl2 (10 mL/mmol amine) and water (2 mL/mmol amine) were added to the residue. The phases were separated and the aqueous phase was extracted with CH2Cl2 (3xc3x975 mL). The combined organic phases were dried (Na2SO4) and concentrated. Purification of the crude material by chromatography provided the free base.
Alternative work-up: the reaction mixture was filtered and concentrated to provide a yellow oil which was purified by chromatography on basic alumina (eluant CH2Cl2 then 20:1 CH2Cl2-CH3OH) and provided the free base as a colorless oil.
General Procedure D: Salt Formation using Saturated HBr(g) in acetic Acid.
To a solution of the free base in glacial acetic acid (or dioxane) (2 mL) was added, a saturated solution of HBr(g) in acetic acid (or dioxane) (2 mL). A large volume of ether (25 mL) was then added to precipitate a solid, which was allowed to settle to the bottom of the flask and the supernatant solution was decanted. The solid was washed by decantation with ether (3xc3x9725 mL) and the remaining traces of solvent were removed under vacuum. For additional purification (where necessary), the solid can be dissolved in methanol and re-precipitated with a large volume of ether. Washing the solid with ether by decantation, followed by drying of the solid in vacuo (0.1 Torr) gave the desired compound.
General Procedure E: SEM-deprotection.
To a stirred solution of the SEM-protected compound (1 equiv.) was added 6N HCl (30 mL/mmol), and the resultant solution was stirred at 50xc2x0 C. for indicated time. The solution was diluted with water (50 mL/mmol), and it was neutralised with NaHCO3 and extracted with EtOAc (3xc3x97100 mL/mmol). The combined organic phases were dried (Na2SO4) and concentrated. The crude material was purified by chromatography.
General procedure F: EDCI Coupling:
To a stirred solution of the amine (1 equiv.), acid (1.1 equiv.), 1-hydroxybenzotriazole (1.1 equiv.), 4-methyl morpholine (1.5 equiv.) in anhydrous DMF (xcx9c0.3 M), at room temperature under nitrogen atmosphere, was added EDCI (1.1 equiv.). The resultant solution was stirred at room temperature for the indicated time. DMF was removed under vacuum. The mixture was diluted with CH2Cl2 (100 mL/mmol), washed with NaHCO3, dried (Na2SO4) and concentrated.
General Procedure G: Mesylation of Alcohols:
To a stirred solution of the alcohol (1 equiv.), and Et3N (1.2 equiv.), in anhydrous CH2Cl2 (xcx9c0.1 M), at 0xc2x0 C. under nitrogen atmosphere, was added MsCl (1.1 equiv.) dropwise. The resultant solution was stirred at the indicated temperature for the indicated time. The mixture was diluted with CH2Cl2 (100 mL/mmol), washed with aqueous NH4Cl, dried (Na2SO4) and concentrated.
General Procedure H: Substitution Reactions with Mesylates.
To a stirred solution of the amine (1.5 equiv.), and Et3N (1.0 equiv.), in anhydrous CH2Cl2 (xcx9c0.2 M), at 0xc2x0 C. under nitrogen atmosphere, was added the mesylate (1.0 equiv.) solution dropwise. The resultant solution was stirred at room temperature for the indicated time. The mixture was diluted with CH2Cl2 (100 mL/mmol), filtered through celite and concentrated. The crude material was purified by chromatography.